John H. Watson — Veteran Chirurgeon and Chronicler

John Watson is a veteran soldier-physician who has seen clever men become useless when blood starts running. He treats wounds first, asks questions second and writes everything down afterward.

He returned from service overseas with scars, practical medical experience and little patience for anyone who treats victims as pieces in a puzzle. In London he works beside Sherlock Holmes, translating deduction into human consequences and recognising injuries that no amount of clever questioning can explain.

At a Glance

Name: John H. Watson
Species: Human
Age: Mid-thirties
Base: London
Role: Chirurgeon, military veteran, witness and chronicler
Alignment: Lawful Good
Campaign status: Alive and active
Campaign use: Healer, medical investigator, reliable witness, patron or grounded companion

Game Statistics

5.5e / 2024
5e / 2014
Pathfinder 1e
D&D 3.5e

5.5e / 2024

John Watson
Medium Humanoid (Human), Lawful Good

Armor Class 16 (brigandine)
Hit Points 86 (12d8 + 36)
Speed 30 ft.

STR	DEX	CON	INT	WIS	CHA
13 (+1)	14 (+2)	16 (+3)	15 (+2)	17 (+3)	14 (+2)

Saving Throws Con +6, Wis +6
Skills Insight +6, Medicine +9, Perception +6, Persuasion +5
Senses passive Perception 16
Languages English, French
Challenge 5 (1,800 XP; PB +3)

Traits

Steady Nerve. Watson has Advantage on saving throws against the Frightened condition.

Field Diagnosis. Watson has Advantage on Medicine checks to determine the cause, age or likely weapon of a wound.

Actions

Longsword. Melee Attack Roll: +5, reach 5 ft. Hit: 6 (1d8 + 2) Slashing damage.

Light Crossbow. Ranged Attack Roll: +5, range 80/320 ft. Hit: 6 (1d8 + 2) Piercing damage.

Battlefield Doctor (3/Day). Watson restores 12 (2d8 + 3) Hit Points to one creature within 5 feet. A creature can benefit from this only once per Short Rest.

Stabilise the Dying. Watson automatically stabilises one creature within 5 feet at 0 Hit Points and may immediately make a DC 15 Medicine check; on a success the creature regains 1 Hit Point.

John H. Watson — 5e / 2014

Medium humanoid (human), lawful good

Armor Class 16 (brigandine); Hit Points 86 (12d8 + 36); Speed 30 ft.; Challenge 2 (450 XP; proficiency bonus +2), reflecting his personal combat role.

STR 13 (+1), DEX 14 (+2), CON 16 (+3), INT 15 (+2), WIS 17 (+3), CHA 14 (+2).

Saving Throws Con +5, Wis +5; Skills Insight +5, Medicine +7 (expertise), Perception +5, Persuasion +4; Senses passive Perception 15; Languages English, French.

Traits

Steady Nerve. Watson has advantage on saving throws against being frightened.

Field Diagnosis. Watson has advantage on Wisdom (Medicine) checks to determine the likely age, cause and weapon of a wound when the evidence is physically available.

Actions

Longsword. Melee Weapon Attack: +3 to hit, reach 5 ft., one target. Hit: 5 (1d8 + 1) slashing damage.

Light Crossbow. Ranged Weapon Attack: +4 to hit, range 80/320 ft., one target. Hit: 6 (1d8 + 2) piercing damage. The loading property applies.

Battlefield Doctor (3/Day). Watson touches a creature within 5 feet and restores 12 (2d8 + 3) hit points. A creature can benefit only once per short or long rest; this extraordinary field-care ability is an original NPC feature, not a standard use of a healer’s kit.

Stabilise the Dying. Watson stabilises one creature at 0 hit points within 5 feet. He may also attempt a DC 15 Wisdom (Medicine) check; on a success, the creature regains 1 hit point.

Original 2014 edition NPC conversion; the 2024, Pathfinder and D&D 3.5e entries and all narrative sections are preserved.

Pathfinder 1e

John Watson CR 5; human expert 4/investigator 3; LG Medium humanoid.

AC 18; hp 57; Fort +6, Ref +5, Will +8. Skills Diplomacy +11, Heal +17, Knowledge (local) +11, Perception +14, Sense Motive +14.

D&D 3.5e

John Watson CR 5; human expert 5/fighter 2; LG Medium humanoid.

AC 17; hp 52. Feats Alertness, Iron Will, Skill Focus (Heal). Skills Heal +16, Listen +12, Search +10, Sense Motive +14, Spot +12.

What Is John Watson Doing Right Now?

Watson is treating a clerk badly beaten after refusing to surrender a packet of copied seal impressions. The injuries tell Watson the attackers wanted information before they wanted silence.

The clerk keeps repeating one phrase: “the professor counts everything.” Holmes believes it points toward Moriarty. Watson is less interested in the phrase than in keeping the witness alive long enough to explain it.

Encounters

Watson is already treating the only surviving witness when armed men arrive to finish the work.
A corpse’s wound suggests a battlefield technique Watson recognises from overseas service.
The party needs medical proof that a prisoner was tortured before giving a confession.
Watson refuses to abandon an injured enemy who may know where Holmes went.

Appearance and Manner

Watson is solidly built, military in posture and more plainly dressed than most London physicians. One old campaign wound troubles him after long rides or cold weather. He listens without interrupting patients and becomes visibly impatient when investigators treat injured people as evidence before treating them as people.

Personality

Courteous, brave and loyal, Watson has a strong instinct for ordinary decency. He admires Holmes while refusing to let brilliance excuse cruelty or carelessness with human lives.

Relationships

Sherlock Holmes: closest friend and intellectual opposite.

Frederick Abberline: values Watson’s medical testimony and reliability.

Veterans: men who served overseas often trust Watson more quickly than they trust city officials.

Equipment and Resources

Medical bag with bandages, needles, splints and herbal antiseptics
Notebook and case records
Brigandine, longsword and light crossbow
Veterans’ contacts and physicians who respect his judgement

Running Watson at the Table

Watson works best when the adventure needs medical truth and human judgement. He can tell the party how someone was hurt, keep a witness alive, recognise military habits and notice when a brilliant plan ignores the frightened person at its centre. He is capable in a fight but never treats violence as the interesting part of a case.

Adventure Hooks

The Beaten Clerk: Watson needs the party to protect a wounded witness overnight.
The Impossible Wound: a corpse bears an injury no known weapon should produce.
Holmes Missing: Holmes vanishes while following Moriarty’s network, and Watson hires people capable of acting without official authority.
The Soldier’s Story: a veteran patient describes the same mysterious symbol found at a London crime scene.

Connected Places and People

Mythical and Historical Context

Dr John H. Watson is a fictional physician and narrator created by Arthur Conan Doyle for A Study in Scarlet (1887). He did not serve in a documented 1454 English army. This setting makes him a medieval chirurgeon and former soldier, giving him contemporary wounds, healing tools and obligations while preserving his friendship with Holmes. The original literary figure can be read in The Adventures of Sherlock Holmes; Britannica’s Watson overview distinguishes his fictional origins. Battlefield Doctor is an original NPC feature, not historical medieval medicine.

Literary Inspiration

John Watson originates in Arthur Conan Doyle’s Holmes stories. This version keeps the veteran physician, loyal witness and chronicler while translating his service and medicine into the fifteenth century.