Daniel Radcliffe is filming scenes for 'Frankenstein' in London.

The 'Harry Potter' star has swapped his short brown hair for dishevelled bob style extensions for his role as Frankenstein's assistant Igor in the latest adaptation of Mary Shelley's novel.

Radcliffe will star alongside James McAvoy (Victor Frankenstein) and former 'Downton Abbey' star Jessica Brown Findlay and previously joked about the difficulty of maintaining his fake hair.

The 24-year-old actor explained: ''I don't mind how it looks but I mind dealing with it. I don't know why any man would have it voluntarily.''

Radcliffe attended the WhatsOnStage Awards last week, where he and his co-star McAvoy were both nominated for Best Actor awards and he admitted that when he's finished working on the fantasy-drama he won't be growing his own hair.

He said: ''The amount of work it takes, having to dry it - doing anything to it is a f**king nightmare. I do have a whole new sympathy for women. I wouldn't be growing my hair this long in my own time.''

'Frankenstein' - which is being directed by Lucky Number Slevin's Paul McGuigan - is expected to be released in January 2015.