The new series Do No Harm premieres this Friday at 9E/6P on SPACE. It’s a story of Dr. Jason Cole, a highly respected neurosurgeon who may suffer from split personality disorder as he juggles his successful life with his dangerous and seductive sociopath alter-ego, Ian Price.

Ahh, the alter-ego, the second self, the other half. Though Clark Kent and Bruce Wayne had theirs donning a cape and saving lives, they more or less had control over what they did and how they affected their day jobs. Other depictions of the alter-ego view it as unpredictable, uncontrollable and dangerous as seen in Do No Harm. This may not be a new idea but it is one that is open to interpretations. Here are some other popular characters whose alter-egos may get the better of them and can be down right terrifying...

Dr. Jekyll and Mr. Hyde
This literary example is no doubt the influence and inspiration for all that followed so it seems fitting to open this list with that. “Strange Case of Dr. Jekyll and Mr. Hyde” was written by Robert Louis Stevenson in 1886 and it turned an ugly face on the mild-mannered.

(It was impossible to find a good quality version of the 1932 film trailer so check out this opening scene from the fantastic 2007 BBC series Jekyll written by Steven Moffat.)

Bruce Banner and The Hulk
It’s always the brilliant scientists who get it bad.

(Hmm, which Hulk trailer to embed... I think it was always obvious.)

The Narrator and Tyler Durden
This movie is 14 years old. I refuse to brand this with a spoiler warning. This movie was actually spoiled for me when I watched it all those years ago. I was told to watch it as if I’m watching Calvin and Hobbes – it was probably just as enjoyable and interesting had I not been spoiled.

Angel and Angelus
Tortured soul. Tainted past. Sought-after redemption. This is how a vampire broods. Angel, the love of Buffy’s (teenage) life, is a vampire with a soul whose murderous alter-ego is forever (or rather occasionally) silenced by the weight of it. But who’s the alter-ego? Angel or Angelus?

(I couldn’t find an appropriate clip that perfectly showed their contrast so here’s a clip of Angel imagining himself dancing)

Smeagol and Gollum
Bruce had gamma rays, the Narrator had insomnia, Angel was de-souled and Smeagol... well, Smeagol had the One Ring.

Honourable Mention:

Steven Urkel and Stefan
I am so, so, so very sorry for adding this...